In the history of the development of saxophones, extra valves were placed on the bell of the saxophone in order to play three extra half-notes below the notes possible to be played with valves only on the body of the saxophone. This meant that three extra keys were required in order to actuate these three extra valves, and it has been customary in recent years to place four keys grouped in a cluster each for actuation by the little finger of the left hand. These were for actuating valves to play the low register notes of G-sharp, C-sharp, B and B-flat. A number of prior art patents have recognized the difficulty of the facile manipulation of these keys, and the transition in actuation from one key to the other. U.S. Pat. No. 2,710,558, for example, was directed to this cluster of four keys, and changed the configuration of these keys somewhat in order to make it easier to have a transistion from C-sharp to B-flat. U.S. Pat. No. 1,828,389 changed the arrangement of a normally closed C-sharp and D-natural valve to ones which were normally open, and then provided a different keying arrangement so that the little finger of the right hand could close both valves with an independent finger-actuated means operable by the little finger of the left hand for separately closing the D-natural valve.
U.S. Pat. No. 2,555,980 provided a movable lug on the saxophone so that the G-sharp, C-sharp, B, and B-flat cluster of keys for the left-hand little finger could have two different modes of operation, as desired by the saxophone player.
U.S. Pat. No. 2,055,382 again discloses this cluster of four keys, and provides a G-sharp trill lever for rapid and repeated operation of the G-sharp valve.
U.S. Pat. No. 1,873,184 recognized the difficulty of obtaining a quick transistion from the C-sharp to the D-natural tone when a saxophone had a normally closed C-sharp valve and a normally open D-natural valve. The patentee's change was to make both the C-sharp and D-natural valves normally open, with the D-natural valve separately controlled from the usual C-sharp key by the left hand and both valves being simultaneously closed by the little finger of the right hand from the ordinary C-natural position.
U.S. Pat. No. 1,632,008 also addressed the problem of the cluster of G-sharp, C-sharp, B, and B-flat keys actuable by the little finger of the left hand, and attempted to solve the problem by providing only three keys instead of four to be actuated.
U.S. Pat. No. 4,148,242 was also concerned with this same cluster of four keys operable by the left-hand little finger, and provided an extra key operable by the thumb of the left hand in order to play the B-flat note in the lower register.
All of these prior patents recognized somewhat the difficulty of easy and rapid manipulation of these four separate keys, G-sharp, C-sharp, B, and B-flat, by the little finger of the left hand; however, none of the patents solved the problem of a rapid change of tone from C-sharp to B-flat or from C-sharp to B.